Air quality monitor



FIG. 1 is a front perspective view of an air quality monitor, showing our new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left-side view thereof;

FIG. 5 is a right-side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines depicting portions of the air quality monitor form no part of the claimed design. 

CLAIM The ornamental design for an air quality monitor, as shown and described. 